Question

by how much does the momentum of a body of mass 3kg change when it's speed decreases from 40m/sec to 10m/sec?

Answer 1

4 times
................

Answer 2

momentum=mass × velocity
so...
change in momentum= mass ×change in velocity

=> change in momentum= 3(40-10)=3×30=90kg m/s

so the change in momentum is 90kg m/s
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initial momentum=3×40=120
finalmomentum=3×10=30
(final momentum) / ( initial momentum ).
= 30/120
=1/4
=> final momentum = 1/4 times initial momentum

hope it helps you..
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